Advancement of Hazard-Consistent Ground Motion Selection Methodology

Performance-based earthquake engineering (PBEE) quantifies the seismic hazard, predicts the structural response, and estimates the damage to building elements, in order to assess the resulting losses in terms of dollars, downtime, and deaths. This dissertation focuses on the ground motion selection that connects seismic hazard and structural response, the first two elements of PBEE, to ensure that the ground motion selection method to obtain structural response results is consistent with probabilistic seismic hazard analysis (PSHA).

Structure- and site-specific ground motion selection typically requires information re-garding the system characteristics of the structure (often through a structural model) and the seismic hazard of the site (often through characterization of seismic sources, their oc-currence frequencies, and their proximity to the site). As the ground motion intensity level changes, the target distribution of important ground motion parameters (e.g., magnitude and distance) also changes. With the quantification of contributing ground motion parameters at a specific spectral acceleration (Sa) level, a target response spectrum can be computed using a single or multiple ground motion prediction models (GMPMs, previously known as attenuation relations). Ground motions are selected from a ground motion database, and their response spectra are scaled to match the target response spectrum. These ground mo-tions are then used as seismic inputs to structural models for nonlinear dynamic analysis, to obtain structural response under such seismic excitations. This procedure to estimate structural response results at a specific intensity level is termed an intensity-based assessment. When this procedure is repeated at different intensity levels to cover the frequent to rare levels of ground motion (expressed in terms of Sa), a risk-based assessment can be performed by integrating the structural response results at each intensity level with their corresponding seismic hazard occurrence (through the seismic hazard curve).